Gallium

This is worth a look : **LINK**

https://www.smithsonianmag.com/innovation/this-liquid-metal-could-transform-soft-electronics-180980043/

… and the related paper is a free download

MichaelG.

Thanks for the link, new use to me.

Thor

Didn't Kawasaki use that for their motorcycle frames?

Nice when useful materials get discovered .

Edited By V8Eng on 07/05/2022 14:49:29

looks great - main producers are China and Ukraine !!

**LINK**

Skip down to :-

GALLIUM PRODUCTION AND CONSUMPTION

World production of primary gallium from bauxite and zinc was about 95 metric tons in 2008, with the top four producers being China, Germany, Kazakhstan and Ukraine.

An interesting metal!

Must not be allowed any where near an aircraft or anything made of alumnium alloy as it forms a grain boundary solution with zero mechanical strength and a little would go a VERY long way!

Same as mercury also bismuth chucked in a brass or bronze pour totally screws it up!

Funny what you remember from Uni all those years ago!

Cheers, Martin

Was not Gallium used for doping Germanium in early semiconductors?

Far to busy, or lazy, to look at Wikapedia.

JA

I recall something called Gallium Arsenide in respect of that..

If it reacts with aluminium like mercury does then it will be deadly with aircraft. We had an aircraft where a stone jar of mercury was smashed in the freight bay and before long we could see daylight through the holes it made in the aircraft pressure skin. Dave W

We were using Gallium slip-rings in satellites 50 years ago.

(Particularly memorable because when we finished doing final tests on one flight model satellite, Charlie the test engineer - under the gun schedule-wise - quickly pulled the power plug assuming power was off. It wasn't. Blew the slip rings to kingdom come. And where are the slip rings? .... buried in the centre of the satellite. A complete strip-down and 6 months delay. Poor Charlie.)

^^^^^ Oops!

At Delft Technical University I had a colleague who studied the interesting ternary phase diagram of the alloy Gallium-Indium-Mercury. He wrote a PhD-thesis about it with a lot of thermodynamical calculations supported by experiments. More than 40 years ago.

I think gallium must be rather poisonous.

Jouke

Without looking it up, I think GaAs is/was used in red LEDs. I know Gallium Arsenide Phosphide (GaAsP) was.

George

vague recollection that Gallium arsenide was used in early, 60s 70s photo cells ? Noel.

Would I be right in assuming that only a few of the contributors to this thread have yet read the paper that was linked in the article ?

MichaelG.

.

Here’s a brief quote from the introduction:

Given these remarkable properties, why is Ga often overlooked aside from its use in semi-conductors (e.g., GaAs, GaN)? This situation can likely be attributed to several factors. Despite being relatively earth abundant, Ga costs ∼$0.25/g (2020 price) since it is produced by extracting Ga oxide as an impurity found in alumina. Plus, there is an overgeneralized historical association of liquid metals (LMs) with toxicity (e.g., the case of mercury). However, probably the most pragmatic explanation as to why Ga is not widely employed commercially is a result of its surface reactivity. A paper published in Science in 1954 stated: “Despite all precautions, this gallium electrode always behaved erratically” (11, p. 390). We now know that this “erratic” behavior is the result of the high reactivity of Ga with its environment. This reactivity most typically manifests itself in the formation of an ∼1–5-nm-thick native oxide that affects the surface chemistry, wetting, and rheology of Ga. Finally, Ga may get overlooked because it can diffuse into the grain boundaries of certain solid metals, such as Al, leading to significant degradation of mechanical properties.

… after which, the paper concentrates upon the exploitation of the mechanical properties of Gallium [which is why I thought it might be of interest here].
.

MichaelG.

Edited By Michael Gilligan on 08/05/2022 14:12:11

Gallium has very interesting properties, so to read.
And its alloys even more I think. But not so easy to work with in my house, garden and kitchen applications I fear.

Yes, in my case.

I had a very quick look at the article and then got on with life.

JA

Gallium Arsenide, an allow of Ga and As, is a III-V semiconductor and widely used in microwave and electro-optic devices. Your mobile phone probably has some in it. Gallium Nitride also a key material in microwave devices and increasingly in power devices for applications such as EVs. A most important element.

Guilty as charged. Should I resign?

George